Crosshead pitman connection



A. ZISKA, JR. CROSSHEAD PJTMAN CONNECTION.

APPLICATION FILED MAR. 22, 1920- 1,397,398 Patented Nov. 15, 1921;

iiilllllfiilillll ADAM ZISKA, JR., 0F MIL'WAUKEE, WISCONSIN, ASSIGNOB TO MILVIAUKEE PRESS 8a MACHINE COMPANY, MILWAUKEE, WISCONSIN.

GROSSHEAD PITMAN CONNECTION.

Specification of Letters Patent.

Patented Nov. 15, 1%21.

Application filed March 22, 1920. Serial No. 367,846.

T 0 all whom it may concern:

Be it known that I, ADAM ZISKA, J12, a citizen of the United States, and resident of Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Crosshead Pitman Connections; and I do hereby declare that the following is a full, clear and exact description thereof.

My invention relates broadly to new and useful improvements in punch press and similar machines, and particularly to an improved type of pitman connection for the tool carrying cross heads thereof.

As at present constructed the pitman connection in this type of machine is extensible and contractible so as to move the tool carrying cross head different distances away from the actuating crank. However, the parts of such pitman connections are so arranged with respect to each other that the construction is relatively non-rigid with the result that considerable wear takes place and lost motion usually occurs. This is very detrimental to the eflicient operation of the several parts of the machine.

Consequently it is the primary object of this invention to provide a simply constructed extensible and contractible pitman connection which will overcome these several disadvantages and will be much more ellicient in other ways than the similar devices of ordinary construction. In other words the improved structure is rigid so that stripping action is prevented which eliminates motion between the different parts, and is strongest in the center where the greatest strain occurs.

A further object of the present invention is to provide an extensible and contractible pitnian having means for pivotally connecting one end of the same to a usual tool carrying cross head, the connection between said end and said means being such that the punch strains imparted to the cross head are evenly distributed and transferred to the pitman.

lVith these general objects in view the in vention resides in the novel features of construction, combination and arrangement of parts which will be hereinafter more particularly described ahd claimed and shown in the drawing wherein:

Figure 1 represents a vertical sectional view through a cross head and illustrating tends.

the manner of connecting the same with a crank by means of my improved pitman, parts of the latter being broken away and in section, and

Fig. 2 isa detail horizontal section taken on the plane of the line 2-2 of Fig. 1.

In the accompanying drawing only so much of a punch press machine is illustrated as to show the application of my invention thereto, and in said illustration the reference character 1 denotes a tool carrying cross head adapted to be reciprocated in suitable guides by means of the rotation of a crank or the like 2. The pitman connecting the cross head and the crank forms the basis of the present invention.

Said invention includes a pitman proper 3 comprising an internally threaded sleeve l open at one end to receive a threaded stem 5 and having a crank bearing at its other end. This bearing consists ofa' sleeve carriedportion 6 and a cap piece 7, these parts being secured together and around the crank 2 by means of clamp screws 8. The threaded stem 5- is designed to be moved into and out of the sleeve l by rotating the same in appropriate directions. The lower or open end of the sleeve 4 is split at one side as at 9 and adjacent thereto are formed clamp ears lOthrough which a clamp bolt 11 e1:-

hus by tightening thebolt 11, the stem 5 may be locked withinthe sleeve after it has been disposed inpredetermined relation thereto. p

The outer or lower end of the stem 5 s shaped to provide a frusto-conical head 12 and a circular radially extending b rring flange 13, the latter being spaced inwardly of the former and positioned between the same and the end of screw threads on the stem 5. The periphery of the flange 18 is provided with a plurality of radially extending sockets i l, in one of which a suitable instrument may be inserted for the purpose of rotating the, stem 5. 1

The lower side of the flange 13 forms a bearing surface for contact with a flat-- surface formed on one face ofa two part connector plate 15, the same also having a socket 16 of frusto-conical shape, the opening of which is surrounded by said iiat surface. Entrance into this socket 16 is attained by the removal of the separable section 155 of the two part connector plate so that the head 12 may be disposed in or removed from the socket. The separable section has a channel 17 receiving a shoulder 18 formed on'the main section of thelconnector plate,

and the two parts of the latter are secured together by retaining screws 19 which are threaded through cooperating bosses 20 as shown in Fig. 2.

The main section of the connector plate has a depending bearing 21. which is located between bearing earsof the tool carrying cross headl and ispivoted thereto by means of a pin orfthe like '23. The lower end of the pitman is thus rotatably and pivotally connected withthe cross head 1. Inuse the flange 13 always remains in engagement with the flat face of the connector plate, and as a result: receivesthe. punch strainimparted to'the cross head. However, regardless of this engagement between these parts,

the stem5 may be readily rotated within the sleeve ,4; when the clamp screw 11 is loose with a consequent adjustment in length of the. pitman.

Various minor changes may be made, in

the form and proportions of the different parts of the invention without departing from or sacrificing any ofrthe advantages thereof.

' carrying member, a crank, andmeanscon- ,necting the same including a connector plate pivoted to tne'tool carrying member, an ex- Iclaimzi l 1. A machine of the class described, a tool tensible and contractible member having one portion connected 'with the crank, nae memher being lengthened-and shortened by rotating a second portion in the first mentioned portion, the second portion havinga fiat bearing surface, and a 'frustoconical head projecting from'the central part thereof, said connector plate 'havingan" annular internal flange with a flat surface engaging Said first mention'edflat surface and anin 'chnedr surface engaging the inclined surface of the frustum.

2. In a machine of theclass described, a

tool carrying member, a crank, and means connecting the same including a two part connector-plate having a fiat bearing surface surrounding a socket therein, one part of the plate being removable to provide access to the socket, an extensible and contractible member having one portion connected with the crank, the member being lengthened and shortened by rotating a second portion in the'first mentioned portion, a head on said,

second portion of the extensible and contractible member androtatable in said socket,

said head being disposed therein when the 1 ne1nber and having a flat bearing surface surrounding a socket therein, one partof the plate being removable to vprovlde access to the socket, an. internallythreaded sleeve open at one end and having its other end connected with said crank, a threaded stem disposed in said'sleeve' and having a portion projected therefrom, a head on the pro jected. end of the stem and rotatably disposed insaid socket, said head being positioned in said socket when the separable portion of the connectorplate is removed, and a'flange extendin'g'radially of said stem,

"said flan e' havin a fiat .face for en a eb b b ment with the bearing surface of the connector plate. V v

In testimony that I- claim the foregoing I have hereunto set my hand at Milwaukee, in the. county. of, Milwaul ee c'onsin; t

i ADAM ZISKA,JR.

and State of Wis- 

